If an electron in an hydrogen atom jumps from an orbit ni=3 to an orbit with level nf=2, the frequency of the emitted radiation is
1. v=36 C5 R
2. v = CR6
3. v = 5 RC36
4. v = 6 CR
In an experiment to determine the e/m value for an electron using Thomson's method the electrostatic deflection plates were 0.01 m apart and had a potential difference of 200 volts applied. Then the electric field strength between the plates is
1. 1×104 V/m
2. 2×104 V/m
3. 4×104 V/m
4. 5×105 V/m
1. | 4λ1=2λ2=2λ3=λ4 |
2. | λ1=2λ2=2λ3=λ4 |
3. | λ1=λ2=4λ3=9λ4 |
4. | λ1=2λ2=3λ3=λ4 |
To explain his theory, Bohr used
1. conservation of linear momentum
2. conservation of angular momentum
3. conservation of quantum frequency
4. conservation of energy
The minimum wavelength of X-rays produced by electrons accelerated by a potential difference of V volt is equal to
1. eVhc
2. ehcV
3. hceV
4. cVeh
The graph between the square root of the frequency of a specific line of the characteristic spectrum of X-rays and the atomic number of the target will be:
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The wavelength of Kα X-rays for lead isotopes Pb208, Pb206, Pb204 are λ1, λ2 and λ3 respectively. Then
1. λ1=λ2>λ3
2. λ1>λ2>λ3
3. λ1<λ2<λ3
4. λ2=λ1=λ3
which of the following is positively charged?
1. α-particles
2. β-particles
3. γ-rays
4. X-rays